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I'm confident in my SRH77A but will put it in ice and boiling water to see if it's accurate. I am right there with you, questioning the delta T. Outside the box, is it possible that there is a temp. Limiter in Ruud units that maybe I'm just unaware of?
Also, thanks for helping me with this!

Just a footnote, the ice water and boiling water are within 10th's of a degree Fahrenheit on the Cooper.
Alright, with the ret. probe @ same locale and the supply probe approx 16" above AHU (being a Ruud this should be out of the sight of the heat strips as they are in the blower shroud. Correct me if I'm wrong) I've got a 30* delta T. On low speed. This is way better @ 684 cfm.

Now, in the case of the 922... Is this incorrect data just a case of being too close to the blower wheel? I did follow the directions of placement of the pitot tube. Remember that I did not do a correct traverse... But would it be this far out of whack, or just another case of user error?

Return temp. Probe was in the pedestal box and the supply was in the side of the supply (7x17) on the 17" side about half way down and 12" high... Now, you got me thinking about how the Ruud's are discharged... Lengthwise, but with only the back part actually discharging the air! maybe just another case of user error, will post when I have new measurements (I'm on location, and toggling between that and Robocop)

User error it is! Thank you guys for the heads up responses. This did raise another question in my head though, and only somewhat related. I am dealing with an up flow unit, on a pedestal box with return cut into the left hand side of the p.b. Seeing how a s.p or pitot tube rather needs to be directed into the airstream... Is the airstream to the left as that's where the air is coming from, or is it facing straight down b/c this is the way it is being pulled? I hope this Ida clear explanation of my question....

User error it is! Thank you guys for the heads up responses. This did raise another question in my head though, and only somewhat related. I am dealing with an up flow unit, on a pedestal box with return cut into the left hand side of the p.b. Seeing how a s.p or pitot tube rather needs to be directed into the airstream... Is the airstream to the left as that's where the air is coming from, or is it facing straight down b/c this is the way it is being pulled? I hope this Ida clear explanation of my question....

A static probe does NOT have to be pointed into the airstream. Pointed up stream, or down stream, works the same.

The holes on the side of the probe just have to be perpendicular to the airflow.

The hard part, as you have probably found, is the air flow in the pedestal box is somewhat turbulent. Trying to find a good place to put the probe is difficult.

I would try to get the probe as close to the bottom of the unit, with the probe facing up/down. You can also try 2-3 different places and average the reading.

Thanks Run... I'd love to take this conversation further if I may.... Taking these CFM calc's one step further, into enthalpy territory.
On high speed I have found that I have 820 CFM. So, I flipped it into cooling mode and took W.B readings in the duct. I've got 62.6 RAWB and 51.5 SAWB. This would give me a delta H of 7.13. So, with the calc. Of 4.5 x cfm x delta H I have 26,332 BTUH from a 25,000 (2 ton) h.p. Is this yet another user error, or is it possible to have a C.O.P of 1.05?
P.S.- This truly is the kind of stuff I think of on a Saturday night nowadays.... I had a moment in my life I refer to as my pretirement, so this is it till I'm eating dirt... Thanks for the responses

Thanks Run... I'd love to take this conversation further if I may.... Taking these CFM calc's one step further, into enthalpy territory.
On high speed I have found that I have 820 CFM. So, I flipped it into cooling mode and took W.B readings in the duct. I've got 62.6 RAWB and 51.5 SAWB. This would give me a delta H of 7.13. So, with the calc. Of 4.5 x cfm x delta H I have 26,332 BTUH from a 25,000 (2 ton) h.p. Is this yet another user error, or is it possible to have a C.O.P of 1.05?
P.S.- This truly is the kind of stuff I think of on a Saturday night nowadays.... I had a moment in my life I refer to as my pretirement, so this is it till I'm eating dirt... Thanks for the responses

Without knowing what evap coil and heat pump you have in this unit, so I can see the exact ratings for this equipment, I would say you are within the margin of error of these calculations.

A measurement error of 1-2ºf on temp, and 30-50 cfm on airflow, will change the total heat content by up to 1000-1500 btuh.